Control valve for pressure regulating and reducing apparatus



June 1, 1937. G. H. SMITH ET'AL 2,082,223

'CONTROL VALVE FOR PRESSURE REGLATING AND REDUCING APPARATUS Filed Jan. Y3l, 1933 2 Sheets-Sheet l GEORG ATTORNEY y June 1, 1937. G, |.|l 5M|TH ET AL 2,082,223

CONTROL VALVE FOR PRESSURE REGULATING AND REDUCING APPARATUS Filed Jan. 3l, 1935 2 Sheets-Sheet 2 557.4: Pl @ya 72 INVENTOR G50/FGF H. 5N/7H.

h//L GgYr f J/vcossso/v ATTORNEY Patented June 1, 1937 CONTROL VALVE FOR PRESSURE REGULAT- ING AND REDUCING APPARATUS George Y, H. Smith, Kenmore,

and Wilgot J.

Jacobsson, Buffalo, N. Y., assignorsg'by mesnev assignments, to Union Carbide and Carbon Corporation, a corporation of New York Application January 31, 1933, Serial No. 654,380

16 Claims.

'I'his invention relates to pressure regulating and reducing apparatus and more particularly relates to improvements in apparatus employing a pilot regulator to control the pressure delivered l by a main regulator.

When regulating and reducing apparatus is employed inconnection with an oxygen cylinder, the low temperature gas which issupplied from the cylinder prevents the -proper operation of m valves and diaphragms ofA rubber composition of the kind used in prior type regulators. The temperature of converted oxygen gas is considerably below 5 C., the point at which rubber loses its resiliency and tends to become glassy and brittle. It is necessary therefore to substitute for the rubber parts of the regulator some material that will be unaffected by extremely low temperatures. I 1

Metal may be used inplace of rubber in the valve seats and diaphragms in prior types of regulators, but a tight sealing eiiect in the valves cannot be accomplished in such regulators unless there is an exact alignment lbetween the valve andthe seat. Perfect axial alignment of the valve parts requires great accuracy of machine work and entails prohibitive cos'ts of manufacture. v It is an object of this invention to provide in a pressure regulating and reducing apparatus all metal valve parts that will seal tightly without necessitating exact axial alignment.

The above and other objects together with the novel features of this invention will be apparent from the following description and the accompanying drawings, of which Fig. 1 is a full view of the apparatus with a section cut away disclosing the connecting nipples between the main regulator and the pilot y regulator;

Fig. 2 is a cross section of the main regulator showing the valve construction;

vFig. 3 is a side view of the assembled apparatus; Fig. 4' is an enlarged View showing a cross section of the pilot regulator; and

Figs. 5 and 6 are views showing the frictional ring which is employed to dampen the action ofl the main valve.

The regulating and reducing apparatus comprises a main regulator M and a pilot regulator P so interconnected that pressure delivered by the pilot regulator governs the main regulator. The main regulator has an inlet I and an outlet 2 connected by a port 3 which is controlled by a main valve V. The inlet I and the outlet 2 are also connected by a by-pass 4 leading through the Apilot regulator and .controlled by a pilot valve T. The control pressure delivered by the pilot regulator is directed Athrough'a passageway or tubing 5 to a main valve operating diaphragm D.

The main regulator M may comprise a body 6 and a cover 1. A partition 8 in the body separates an inlet chamber A from an outlet cham-` ber B and has a central opening 9 for receivinga nozzle I0. I'he nozzle is provided with a. large diameter bore or port 3 and with a hexagonal shoulder having a raised sealing surface or valve seat II. The nozzle may be threadedly secured within the opening 9 by cooperating screwl threads I2 and i3. A bore I4 may be made in the wall of the body 6 in alignment with the nozzle Ill for guiding a valve head retainer I5, valvehead I6 and closing spring iT.

In accordance with this invention the valve' head vIii Acomprises a 'relatively thick metal 'disc having a raised annular sealing area or face I8 of substantially thesame diameter and width as the valve seat Ii. The edge of the valve head I5 has a convex curvature. It fltswithin a. recess in a cage i9 having a concave curvature'which receives the convex curvature on the valve head IB and which forms a part of the valve head retainer` I5. The side of the valve head I6 opposed to the valve face has a raised central portion that is provided with a convex surface 20 bearing against a fiat area of the valve head retainer I5.

Valve head IG is therefore slightly rockable within the retaining cage I9 so that the annular valve face I8 and valve seat II may be brought intouniform contact even though the plane of the valve face and the plane of the valve seat may not' have been parallel with each other when the valve was assembled.

The valve head retainer I5 may have a number of spaced annular ribs 2| for reducing the friction between the wall of the bore I4 and the 1 retainer when the retainer is moved by the spring. I1 in opening and closingthe main port. The

stant amount of friction to prevent chattering of the main valve.'` A suitable cap 24 may be provided to close oi the outer end oi; the bore i4. A

I1. The spring l1 is comparatively weak in order that the effect cf spring pressure on the.

action of the main valve may be reduced.

The main regulator body 6 is provided with an annular rim having its center axisin alignment with the nozzle I0 and the bore I4. A cover, as a curved cover 1, may be mounted on the rim 25 andclinch the outer edge of the main operating diaphragm D between a rounded lip 26 on the rim and a cooperating annular edge 28 on the under side of the cover. When so positioned, suitable stud bolts 29 maybe screwed into tapped drillings '30 in the rim 25 and nuts 3| may be employed to bring the body and cover tightly together. The diaphragm D forms a chamber 32 under the cover and a space 33 between the body 6 and the diaphragm. The latter space 33 is connected with the outlet chamber B by a port 34 so that delivery pressure may act against the diaphragm D. The diaphragm is supported against excessive exing by plates 35 and 36 which are joined together by means of a stud 31, forming an integral part of the plate 35, and by a nut 38. Each of the plates has a central hub. Between these hubs the diaphragm D is clamped whenthe nut 38 is tightened on the stud 31. vA

raised annular lip on the outer edge of each.

plate acts as a partial stop to the flexing-action of the diaphragm when under pressure.

A drilling 39'is made in the wall of the body between chamber Band space 33 and in alignment with the Yvalve port 3. A iioating valve stem 40 slides within the drilling 33 without appreciable friction and extends from the base of plate 35 to the valve head I6. When the valve V is closed, the stem 40 bears lightly against the diaphragm supporting plate, and the diaphragm D maintains a normal ilat position. A number of :rectangular vanes 4I may be welded to the stem 4U where it passes through the nozzle or port 3 in order to align the stem centrally against the valve head I6. .The guiding vanes slide against the Wall of the port 3 and move with little or no friction when the valve is operated.

As shown in Fig. 1 an opening 4a is made in the Wall of inlet chamber A for-communicating with the pilot regulator P, and an opening 4b is 'made in the wall of outlet chamber B for completing the by-pass 4 around .the main valve V from the inlet chamber A to the delivery chamber B through the pilot regulator. The openings 4a and 4b are counterbored so as to receive one end of the beveled nipples 42 and 43. A suitable packing material 45 is provided in the counterbores and is compressed by the beveled ends of the nipples to form gas-tight joints when the regulators are assembled. The other ends of the nipples 42 and 43 are connected to the pilot regu lator P. .l

The pilot regulator P as shown in Fig. 4 comprises a body 46 preferably cylindrical in shape and provided with lugs 41, 48 and 49 for attachlng the body 46 to the main regulator bodyy 6 bore of the inlet nipple provides aninlet cham- Iber for the pilot regulator.

`nipple forms a 'shoulder which is welded o-r otherwise secured to the-pilot regulator body. The bypass passage 4 in the nipple is tapped at the in- A-lange 5I on the let end to receive a screenretainer 52 and a ne mesh wire screen 53 forremoving foreign particles fromthe gas. A small nozzle 54 is screwed linto a tapped drilling in the upper side of the nipple to provide a communication between the passage in the nipple and the pilot delivery chamber C.

The pilot regulator comprises also a valve mechanism operated by a pilot diaphragm 56, and a pressure responsive mechanism operated by a secondary diaphragm 51 and an adjustable spring 58. The pilot valve mechanism and the pressure responsive mechanism are interconnected by a yoke 59 so that movements of the secondary`diaphragm 51 and the adjustable spring 58 also'operate the pilot valve.

The pilot valve mechanism may comprise a valve head 6D having a raised sealing area or valve face El and a convex base 62 as on the main valve head I6. The valve face 6I co-.operates with a valve seat on the nozzle 54 when the pilot valve is closed. A valve retaining'me'mber T provided with a concave recess 63 holds the valve head rockably positioned so that the valve head may adjust itself and make full contact with the nozzle although not in exact alignment as in the .case of the main valve V. A threaded area on the retaining member T is screwed into a cylindrical portion of the yoke 59 by means. of an upwardly extending stem provided with a screw slot 64. f/A light valve closing spring 65 is supported between the stem and cylindrical Wall of the yoke and is compressed against a suitable cap '66 having a shallow drilling 61 for holding the end of the spring. f

The yoke 59 is kept in a central position in the pilot regulator by an annular perforated diaphragm 68 iitting around the upper end of the yoke and resting against a shoulder 63 thereof and a corresponding shoulder 10 inthe body 46. Spring Wire retaining rings 1| and 12 respectively support thediaphragm 68 against the inner and outer shoulders. The yoke is shaped so as to pass around the nipple 42`and have 'its upper end and its lower end centrally alignedvwithin the pilot v`thereof against the beveled shoulder 14 in the body.` When so clamped the outer edge of the diaphragm will bend readily under pressure exerted from above. Diametrically opposed slots 11 are made in the clamping'ring in order to screw the same into place. The end of the yoke rests Within: a close fitting, cup-shaped washer 18y having a stem 19. A chamber C is made in the upper part of the pilot regulator by the pilot diaphragm, and in order to complete the by-pass from nipple 42 to nipple 43 in axial drilling 80 is made in the lower endv of the yoke and a small bleeder passage 8l is drilled radially in the side of the yoke below the nut 13.

The secondary or pressure-responsive diaphragm 51 is supported at the center by the stem -19 of Washer 18 and by a guiding member 82. 'Ihe guiding member 82 has a shallow hole in the center for receiving the stem 19, and a raised upper area 83A which bears against a substantial part of diaphragm 51. lThe* under side'of guiding member 82 may be provided with a shoulder 8l resting on the upper end of the adjustable spring 58. Av cap 85 encloses the spring 58 and bears against a beveled shoulder 86 in the body when threadedly connected by screw threads 81 and 88. The annular end of the cap is similarly beveled and clamps the outer edge of diaphragm 51 against the shoulder 86 so that the diaphragm tends to bend downward when'the valve is in a closed position. 'I'he 'wall of the cap 85 is of greater width than the shoulder 86 and supports an additional area on the under side of the diaphragm. The unsupported area. of the secondary diaphragm 51 is slightly greater than that of the pilot diaphragm 56, allowing fluctuations of pressure in the space between the two daphragms to have a greater effect on the secondary diaphragm than on the pilot diaphragm 56..

The cap 85 may have a shoulder 89 extending under the outer edge of the vguiding member 82 and acting as a stop to hold the member in ,place against the end of the yoke when not under pressure of the adjusting spring 58. The cap is preferably provided with a number of breather ports 90 which admit atmospheric pressure to the under side of diaphragm 51. The spring may be a relative strong helical coil of spring wire com` pressed between the guiding member and a spring adjusting washer 8l. In order to vary the com.- pression of spring 58, the spring adjusting washer has ashoulder bearing against the end of the spring and an inner cylindrical' bore provided with a chamfered base 92 against which a threaded stem 83 may be screwed. The stem 83 cooperates with a drilled and tapped opening 94 in the end oi' the cap and has a convenient n ut at the outer end for adjusting the position lof the stem and the spring. The end of the stem bearing against the washer 9| is machined to form a socket for holding a ball bearing 95 that reduces friction at this point. A ring washer 96 is secured to the stem near the upper end in order to prevent the stem from being screwed out ofthe cap when the spring is decompressed. A suitable lock nut 81 may be employed to maintain any desired setting ofthe adjustable spring and stem.

The main chamber C in the pilot regulator is connected with the chamber 32 between the cover and the main diaphragm D in the main regulator so that pressure delivered by the pilot valve may act on the main diaphragm D. A drilling 88 is made in the sideoi chamber C and a drilling 98 is made in the side of the cover 1, which drillings are tapped to receive elbows r nipples |86 and Ill that may be interconnectednby a tube 5.

`Suitable aring nipples may be welded to either.

end of the tube, and union fittings |02 and |88 may lbe employed in completing the connection. The valve heads and nozzles in both regulators are preferably-made of a nitrided ferrous alloy that provides sealing surfaces of hard wearing, non-corrodible or corrosion-resistant metal. The valve face and the valve seat are ground to optical fiats'to insure a complete line of contact between the valve face and the seat at all points around the face and the seat.' Itis also preferred to use a exlble sheetof a suitable noncorrodible (corrosion-resistant) metal or alloy such as Everdur for the dlaphragms.

In constructing the valve parts the ratio be-` .tween the area within the seal or une of contact between the valve face and its seat and the area of the active portion of the diaphragm in each regulator is made substantially equal. 'I'he aca rising discharge characteristic.

tive area of the diaphragms relates to the area affected by pressure. The main and pilot valves are constructed to open in opposite directions in respect to the flow of the Yfluid therethrough.

When the main regulator and the pilot regulator valves are so constructed and are proportioned in respect to their dlaphragms as stated, the pressure delivered by the pilot valve to operate the chamber falls with a falling inlet pressure. This Vcharacteristic is herein called a falling discharge characteristic. The main valve is constructed to open against inlet pressure so that a falling inlet pressure on the main valve tends to increase the main delivery pressure.` This tendency is called The effect of the falling characteristic of the pressure deliveredlto the main operating diaphragm chamber 3,2 by the pilot regulator counteracts the rising discharge tendency of the main valve and causes the apparatus todevelop a substantially constant discharge characteristic, or constant delivery pressure regardless of a falling inlet pressure.

The pressure-responsive mechanism including the secondary diaphragm 51 reacts to changes in the flow of gas in the outlet chamber Bof the main regulator. These changes, which are inomentary .pressure variations, are communicated to the diaphragm 51 and immediately adjust the position of the pilot regulator valve so that the urne of gas without substantially affecting the outlet pressure.

Although we have described a preferred formof this invention it should be understood that changes may be made in the form as shown without departing from the scope of this invention as set forth in the appended claims.

We claim: 5 n

1. A uid control valve comprising a body having an' inlet and an outlet; a partition within the body and havinga port connecting .the'inlet with' the outlet; avalve-seat surrounding said port and being provided with a narrow raised sealing slirface; a rockable valve head having va valve face with a similar sealing surface adaptvalve head toward the valve seat; and means inclu'ding a cage having a portion cooperating with the convex area on the rear surface of Isaid sure so that the delivery pressure in the pilot valve-head and adapted for supporting said valve head at its outer peripheral margin and for rockably adjusting the said head to align the sealing surface of the valve face with said valve seat sealing surface.

2. A fluid control valve'comprising a body hav ing-an inlet and an outlet; a partition within the body having a port connecting the inlet and the outlet; a nozzle secured within the port and having'a raised valve seat; a valve head provided with a valve facje 'having a similarly raised sealing surface adapted to contact with the valve seat on the nozzle, said`valve head having a convex' area on the side opposite the valve face lvsealing surface; a movable guide member having annular ribs thereon slidable in the valve body,

the said member being adapted for guiding said valve head toward and away from the said noz having a narrow raised sealing surface voijhard 4 metal adapted to' contact with sai-d valve seat' sealing surface; a valve -he'ad retaining member for rockably supporting and adjusting said valve head to align said valve face sealing surface with said valve seat sealing surface; and a stem adapted for transmitting movement of a pressure-responsive means to said valve head, the head contacting directly with and being rockable independently of the stem.

4. A fluid control valve comprising a body having a partition provided with a valve port; a valve seat surrounding said port, having a raised sealing surface; a rockable valve head having a similar sealing surface adapted to contact with said valve seat surface, said valve head having a convex base; means slidably connected with said body and in approximate alignment with said` nozzle; means attached to said slidable means for supporting said valve head whereby said valve head may be rockably self-adjusted for full line contact between the sealing surfaces when the valve port is closed; a stern adapted for transr mitting movement of a uid pressure responsive means to said valve head; and means for guiding the stem in the valve port. Y

yE. A fluid control valve comprising a body having .a partition provide-d with a valve port; a valve seat member having a sealing surface of hard metal surrounding said port; a valve head having a sealing'surface of hard metal adapted to contact with said valve seat-sealing surface; a bore within said body in alignment with said valve. seat member; spring-pressed slidable means including a cylinder within said bore for 'supporting' said valve head; said cylinder having a groove in its outer peripheral wall, and having in its forward wall adjacent the valve head a recess provided with curved side wa'lls for securing in the recess the said valve head at the peripheral margin thereof for limited rocking movement of the said head; and an annular ring bent sinusoidally to fit within said groovel said ring bearing against the wall of said bore for producing a substantially constant amount of friction.

6. In a pressure regulating and reducing apparatus, the combination of a' body having a partition provided with-a valve port and a bore in approximate alignment with saidvalve port; a

nozzle secured in said partition and forming the walls of said port; a valve seat on said nozzle having a sealing surface surrounding said port; a valve head having a sealing surface adapted to contact with said valve seatl sealing surface; a spring-pressed slidable means contacting the sides. of said bore for rockably supporting said valve head; a floating valve'stern arranged withinthe nozzle and bearing against the valve head and adapted to transmit to the latter the movement of a fluid-pressure responsive means, and means adapted to align the stem axially in the;l nozzle and to guide the end of the stem against the center of said valve head.

' aoaaeas 7. A iiuid control valve comprising a body having an inlet and an outlet; a partition within the body between the inlet and the outlet; said partition vhaving a port therethrough adapted to connect said inlet with said outlet; `a valve seat member having a sealing surface surrounding said port; a valve head having a face provided with a sealing surface vadapted to contact with said valve seat sealing surface; a bore within said body in alignment with said valve seat; a

Aspring-pressed slidable cylinder. within said bore for supporting said valve head, said cylinder having an annular ,groove in its external wall; and an annular resilient ring bent sinusoidallyl to fit within said groove, saidring bearing longitudinally against the opposed side walls of said groove and radially against said bore.

8. A fluid control valve comprising a body having an inlet and an outlet; a partition within the body between'the inlet and the outlet, said partition having a port therethrough adapted to connecthsaid inlet with said outlet; a valve seat Surrounding said port; a valve headhaving a face adapted to contact with the valve seat; a bore within said body in alignment with said port; and a spring-pressed slidable cylinder within said bore for rockingly supporting said valve head, said cylinder having open annular grooves in its external surface facing the wall of Said bore, the annular ribs formed by said grooves bearing frictionally against the bore.

9. In a pressure regulating and reducing apparatus the combination of a body having a partition provided with a valve po-rt; a nozzle secured to said partition and forming the walls of said port; a valve seat on said nozzle having a raised v sealing surface of hard metal surrounding said port; a valve head comprising a similar raised sealing surface of hard metal adapted to contact with said valve seat sealing surface; a bore within said body in approximate alignment with said nozzle; means including a spring-pressed cylindrical member within said bore for rockably supporting said valve head; a valve stem centrally guided within the nozzle and bearing against said valve head; a flexible diaphragm arranged within said body; and flex-limiting means for supporting said diaphragm from both sides over a substantial area at the center thereof and bearing against the valve stem.

l0. In a pressure regulating and reducing apparatus the combination of a body having a partition provided with a valve port; a nozzle secured to said partition and forming the walls of ysaid port; a valve seat on said nozzle comprising a raised sealing surface surrounding said port; a valve head having a similar raised sealing surface adapted to contact with said valve seat seal` ing surface; a bore within said body in approximate alignment with said nozzle; means including a spring-pressed cylindrical member within ing movement between said stem and said diaphragm yand head; respectively; and means for supporting vs ai'ddiaphragm over a substantial area atthe center .fthereofand for limiting the flexing of the diaphragm at the said area.

'v -11. A fluid control valve comprising a body having'an' inlet and an'outlet; and means for `'forming a fluid-tight separation between said k inlet and said outlet. said means comprising a I wall, a port in said wall, a valve seat member surrounding said port and having a raised sealing surface, a rockable valve head having a valve face with a similar sealing surface adapted to contact with said valve seat sealing surface,

means including a convex area on the rear of said valve head for supporting and rockably adjusting said valve head to align said valve face sealing surface with said valve seat sealing surface, means for urging the rockable valve head into contact with the valve seat, and means guided within the said port for applying force to the said rockable valve head opposing the last-named' cluding a spring for urging the valve head toward the valve seat. Y

13. A fluid control valve comprising a body having a partition provided with a. valve port; a valve seat member having a metal sealing surface surrounding said port; a valve head having a metal sealing surface adapted to contact with said valve seat sealing surface; a bore within said` body in alignment with said valve seat memberf spring-pressed longitudinally slidable means including a cylinder within said bore for supporting said valve head at the outer peripheral margins of the latter; said cylinder having at least one annular rib and a groove in its external wall; and

an annular ring bent sinusoidallyffto nt within said groove, said ring bearing uniformly against the wall of said bore for producing a substantially constantamount of friction.

14. A fluid control valve comprising'a body having a partition provided with a valve port; a,

valve seat member having 'a metal sealingsurface surrounding said port; a valve head having a metal sealing surface adapted to contact with said valve seat sealing surface; the said sealing surfaces being ground respectively to optical flats:

\ Patent No; 2,082,223.. y

of the above numbered patentY requiring correction as follows; s econd column, line 50. forthe word "nut" read clamping ring; line 66,

'a bore withmsaid body in alignmentfwxth said I valve seat member; spring-pressed slidable means including a cylinder within said bore for supporting said valve head; said cylinder having a groove in its external wall; and an annular ring bent sinusoidally to fit within said groove, said ring bearing uniformly against the wall of said bore for producing a substantially constant amount of friction'.

15.'A' fluid control valve comprising a body having a partition provided with a valve port; a valve seat member having a sealing surface surrounding said port; a valve head having a sealing surface adapted to contact with said ,valvev seat' sealing surface, and having the opposite surface provided with a convex central portion; a 'bore within said body in alignment with said valve seat member; spring-pressed. longitudinally slidable means including a hollow cylinder within said bore for supporting said valve head; said cylinder having a groove in its external wall; and sinusoidal dampening means for suppressing humming noise and disposed at the surfaces of lcontact of the saidcylinder and the wall of said bore', and bearing uniformly against the wallof said bore for producing a substantially constant amount of friction; the said cylinder having an end thereof adapted to house the valve head and to support it at the peripheral margin and at the said convex central portion for limited rocking movement.

16. A fluid control valve comprising a body having a partition provided with a valve port; a valve seat member having a narrow metal sealing surface surrounding said port; a valve head having a narrow metal sealing surface. adapted to contact with said valve seat-sealing surface; a bore within said body in alignment with said valve seat member and spring-pressed longitudinallymovable means including a cylinder within said bore-forsupportin'g said valve head; said cylinder having an annular-groovein its outer peripheral wall, and having in its forward wall adjacent the valve head a recess provided with curved side walls adapted for securing in the said recess the said valve head at the peripheral margin of the latter for limited locking movement of the said head.

GEORGE H. SMITH.

WII-GOT J'. JACOBSSON.

' CERTIFICATE or coRREcrIoN,

June 1,V 1957.

-cEoRGE H. sufra, Ar..

I t is hereby certified that `error appears `in fthe printed specification Page 2..

rsi-jin" .read an; and that the said Letters Patent should be? readwith l (sali)` same may' conferir to. the record of the sllenry Van Arsdale -i vloting Commissioner of Patents'.

I wall, a port in said wall, a valve seat member surrounding said port and having a raised sealing surface, a rockable valve head having a valve face with a similar sealing surface adapted to contact with said valve seat sealing surface,

means including a convex area on the rear of said valve head for supporting and rockably adjusting said valve head to align said valve face sealing surface with said valve seat sealing surface, means for urging the rockable valve head into contact with the valve seat, and means guided within the said port for applying force to the said rockable valve head opposing the last-named' cluding a spring for urging the valve head toward the valve seat. Y

13. A fluid control valve comprising a body having a partition provided with a. valve port; a valve seat member having a metal sealing surface surrounding said port; a valve head having a metal sealing surface adapted to contact with said valve seat sealing surface; a bore within said` body in alignment with said valve seat memberf spring-pressed longitudinally slidable means including a cylinder within said bore for supporting said valve head at the outer peripheral margins of the latter; said cylinder having at least one annular rib and a groove in its external wall; and

an annular ring bent sinusoidallyffto nt within said groove, said ring bearing uniformly against the wall of said bore for producing a substantially constantamount of friction.

14. A fluid control valve comprising'a body having a partition provided with a valve port; a,

valve seat member having 'a metal sealingsurface surrounding said port; a valve head having a metal sealing surface adapted to contact with said valve seat sealing surface; the said sealing surfaces being ground respectively to optical flats:

\ Patent No; 2,082,223.. y

of the above numbered patentY requiring correction as follows; s econd column, line 50. forthe word "nut" read clamping ring; line 66,

'a bore withmsaid body in alignmentfwxth said I valve seat member; spring-pressed slidable means including a cylinder within said bore for supporting said valve head; said cylinder having a groove in its external wall; and an annular ring bent sinusoidally to fit within said groove, said ring bearing uniformly against the wall of said bore for producing a substantially constant amount of friction'.

15.'A' fluid control valve comprising a body having a partition provided with a valve port; a valve seat member having a sealing surface surrounding said port; a valve head having a sealing surface adapted to contact with said ,valvev seat' sealing surface, and having the opposite surface provided with a convex central portion; a 'bore within said body in alignment with said valve seat member; spring-pressed. longitudinally slidable means including a hollow cylinder within said bore for supporting said valve head; said cylinder having a groove in its external wall; and sinusoidal dampening means for suppressing humming noise and disposed at the surfaces of lcontact of the saidcylinder and the wall of said bore', and bearing uniformly against the wallof said bore for producing a substantially constant amount of friction; the said cylinder having an end thereof adapted to house the valve head and to support it at the peripheral margin and at the said convex central portion for limited rocking movement.

16. A fluid control valve comprising a body having a partition provided with a valve port; a valve seat member having a narrow metal sealing surface surrounding said port; a valve head having a narrow metal sealing surface. adapted to contact with said valve seat-sealing surface; a bore within said body in alignment with said valve seat member and spring-pressed longitudinallymovable means including a cylinder within said bore-forsupportin'g said valve head; said cylinder having an annular-groovein its outer peripheral wall, and having in its forward wall adjacent the valve head a recess provided with curved side walls adapted for securing in the said recess the said valve head at the peripheral margin of the latter for limited locking movement of the said head.

GEORGE H. SMITH.

WII-GOT J'. JACOBSSON.

' CERTIFICATE or coRREcrIoN,

June 1,V 1957.

-cEoRGE H. sufra, Ar..

I t is hereby certified that `error appears `in fthe printed specification Page 2..

rsi-jin" .read an; and that the said Letters Patent should be? readwith l (sali)` same may' conferir to. the record of the sllenry Van Arsdale -i vloting Commissioner of Patents'. 

